Showing papers on "Bridge circuit published in 2003"

Inverter for transforming a DC voltage into an AC current or an AC voltage

Abstract: Between two direct current (DC) connections in a parallel wiring structure there is a intermediate power store and a bridge circuit with two parallel branches (A/B,C/D), to each of which are wired rectifier diodes (DA,DB,DC,DD) in parallel. Certain rectifier diodes (DE,DF) link to each other in single connecting paths (9,10) in an opposed conducting direction. Each of two alternating current (AC) connections links individually via a connection node to one of the parallel branches between two switch units by means of a connecting wire, in which each has inductive chokes (L1,L2).

Power supply with a direct converter

Abstract: The invention relates to a power supply with a direct converter provided in the form of a two-phase or three-phase bridge circuit. According to the invention, the bridge branche (20) of the direct converter consists of a serial connection of any number of identical two-terminal networks (10) each having the following characteristics: The two-terminal networks (10) each have at least one switching state (I), in which their terminal voltage (UX) takes on positive values independent of the magnitude and polarity of the terminal current; the two-terminal networks (10) each have at least one switching state (II), in which their terminal voltage (UX) takes on negative values independent of the magnitude and polarity of the terminal current; the two-terminal networks (10) have at least one internal energy store.

Vibration control of structures with self-sensing piezoelectric actuators incorporating adaptive mechanisms

Abstract: In a piezo-based self-sensing actuation (SSA) configuration, the control signal is mixed with the signal due to mechanical response The success of SSA relies on the extraction of that mechanical response from the mixed signal Owing to the relatively high amplitudes of those two signals and the ambience varying property of the equivalent capacitance of the piezoelectric element, a fix designed bridge circuit in the SSA configuration would extract a corrupted mechanical response under the variation of the piezoelectric capacitance This would degrade the system performance or even destabilize the closed loop system In this paper, an adaptive compensation is proposed to combine with the SSA technique to develop a vibration controller that is capable of extracting the true sensing signal due to structural deformation The results of this study illustrate that the combined design can simultaneously suppress the structural vibration during the piezoelectric capacitance variation

Magnetoresistive linear position sensor

Abstract: A sensor method and system for detecting linear position. At least one sensing bridge circuit (400) can be configured from at least two separate sensing bridges that share a common geometrical center and are rotated from one another to provide signal offsets thereof. At least one magnet (102) has a north pole (116) and a south pole (118) thereof, such that the sensing bridge circuit is disposed a particular distance from the magnet to provide sinusoidal shaped signals, which can be utilized to determine travel and thus a linear position associated with the magnet.

Method and circuits for testing high speed devices using low speed ATE testers

Abstract: A bridge circuit disposed between a device under test (DUT) and conventional automatic test equipment (ATE) extends the performance of the ATE. The bridge circuit allows the ATE to test ICs capable of operating at frequencies above the ATE's normal performance limits. In some embodiments, the bridge circuit also extends ATE functionality, providing frame alignment and automatic test-vector generation, for example, and can increase the number of available test channels.

Variable resistance sensor with common reference leg

Abstract: A resistive bridge sensor circuit that includes a first resistive bridge circuit having a first variable resistance resistor and a second resistive bridge circuit having a second variable resistance resistor. The first and second resistive bridge circuits share at least a portion of a common reference leg that sets a resistance of a first and second variable resistors. The common reference leg or a portion of the common reference leg is alternately switchably connected to one of the first and second resistive bridge circuits.

Motor driving apparatus

Abstract: In a motor driving apparatus, a driving circuit drives a plurality of loads contained in a plurality of motors, and a control circuit controls the driving circuit to sequentially drive the motors. The driving circuit is provided with at least n+1 number of output terminals in order to connect thereto n number of loads, each of the output terminals being led out from a node of a PNP type transistor and an NPN type transistor connected in series through the node in such a configuration that each pair of the output terminals adjacent to one another constitute a bridge circuit assigned to drive one load. The control circuit turns on and off the PNP and NPN type transistors of the bridge circuit to thereby energize the load in either of a normal direction and a reverse direction. A particular one of the output terminals is led from a node of a particular PNP type transistor and a particular NPN transistor, one of which is driven by a constant electric current through a feedback loop and the other of which is driven by a constant electric current through an open loop. The particular output terminal and another output terminal adjacent thereto are paired to constitute a particular bridge circuit for driving a particular load by the constant electric current through either of the feedback loop and the open loop properly depending on whether the particular load is energized in the normal direction or the reverse direction.

Inverter and motor control method

Abstract: PROBLEM TO BE SOLVED: To detect a motor current accurately by detecting a current on the DC side through one shunt resistor in an inverter for driving a motor. SOLUTION: A switch circuit 101 comprises a bridge circuit for phase U to phase W. A DC power supply 111 is connected to the input side of the switch circuit 101 and a motor 112 is connected to the output side thereof. A shunt resistor R is provided on the input side of the switch circuit 101 and combined currents of phase U to phase W flow through the shunt resistor R. A current detection circuit 10 detects the motor current by utilizing the shunt resistor R upon elapsing a predetermined time after on/off switching timing of a switching element constituting the switch circuit 101. A control circuit 11 creates a PWM signal for controlling the switch circuit 101 on the basis of a detected motor current. COPYRIGHT: (C)2005,JPO&NCIPI

Method and apparatus for measuring a fluid characteristic

Abstract: A tube through which fluid flows is installed in a fluid system. A piezoelectric driver is mounted on the exterior of the tube. A piezoelectric sensor is also mounted on the exterior of the tube. A feedback loop from the sensor to the driver is adapted to cause vibrations in the tube at its resonant frequency or a harmonic thereof. One or more strain gauges mounted on the exterior wall of the tube sense the strain exerted on the exterior wall by the pressure of the fluid flowing through the tube. A temperature sensor mounted on the exterior wall of the tube senses temperature. A microprocessor determines the density of the fluid flowing through the tube responsive to the piezoelectric sensor, temperature sensor and the one or more strain gauges. The one or more strain gauges comprise a bridge circuit. Strain gauges comprise two arms of the bridge circuit and temperature dependent resistors comprise the other two arms of the bridge. The output from the one or more strain gauges is used to correct the frequency reading given by the piezoelectric sensor.

Circuit arrangement for the actuation of an electric-motor drive, in particular a pump drive, in a large domestic appliance

Abstract: In order to be able to operate variably and in particular in an optimised manner in a large domestic appliance not only the main drive ( 17 ) thereof but also the auxiliary drive ( 24 ) thereof, without having to substantially increase the overall control complication and expenditure of the appliance required for that purpose, the main and auxiliary drives ( 17, 24 ) are fed from the same dc voltage intermediate circuit ( 19 ) which is provided only once, by way of change-over switch sets ( 12 ), by half-bridge circuits ( 21, 21′ ). For that purpose it can be provided that the frequency converter ( 15 ) with its bridge circuit ( 21 ) for the main drive ( 17 ) is switched over in single-pole or multipole mode to the rotary field motor ( 23, 25 ) of the auxiliary drive ( 24 ) by way of a change-over switch set ( 12 ) connected in its output-side motor lines ( 13 ); or in the frequency converter ( 15 ) two half-bridge circuits ( 21, 21′ ) which are associated with the main and the auxiliary drives ( 17, 24 ) are operated in parallel from the dc voltage intermediate circuit ( 19 ). Such alternative circuit configurations, with the frequency converter ( 15 ) which in itself is designed for the main drive ( 17 ), by way of control of the rotary speed or the direction of rotation of the auxiliary drive ( 24 ), permit the implementation of additional flow-dependent functions such as for example flushing a washing machine pump free of washing threads and fibres caught therein.

Electronically commutated dc motor comprising a bridge circuit

Abstract: Disclosed is an electronically commutated DC motor comprising a stator which is provided with at least one stator winding (22, 24, 26), a rotor (28) which electromagnetically interacts therewith, a positive and a negative DC line (76, 78) supplying the motor (20) with current, particularly from a battery (77), a full-bridge circuit (74) which controls the current in the at least one stator winding (22, 24, 26) and is provided with a plurality of bridge branches, each of which comprises an upper bridge transistor (66, 80, 86) controlling the current from the positive DC line (76) to a connection (68; 82; 88) that is assigned to said stator winding (22, 24, 26) and a lower bridge transistor (70, 84, 90) controlling the current from the respective connection of the stator winding to the negative DC line (78). The inventive motor also comprises an arrangement generating a plurality of rotor position signals and an arrangement controlling a given bridge transistor by interlinking rotor position signals that are assigned thereto, said rotor position signals being interlinked by a control transistor (60). A first rotor position signal (H1) can be fed to the base of said control transistor (60) while a second rotor position signal (H2) can be fed to the emitter thereof. The collector signal thereof controls the given bridge transistor (66). Also disclosed is a circuit comprising a half-bridge.

Thermal type flow rate detector

Abstract: A thermal type flow rate detector includes: a bridge circuit constructed by upstream side and downstream side temperature detecting elements for detecting a temperature of fluid flowing from the upstream side to the downstream side, and fixed resistors; and a temperature difference controlling circuit for continuously supplying an electric power to upstream side and downstream side heat generating elements so that a temperature difference between the temperature detecting elements becomes a predetermined value. The temperature difference controlling circuit includes: a differential amplifier connected to the bridge circuit; a first constant voltage power supply; a second constant voltage power supply having a lower constant voltage than that of the first constant voltage power supply; and the upstream side and downstream side heat generating elements.

Control device for internal combustion engine

Abstract: PROBLEM TO BE SOLVED: To reduce loss generated in a switch element of a constant voltage power supply circuit which provides a microprocessor controlling an engine with power supply voltage at high engine speed. SOLUTION: A rectifying circuit 2 for rectifying output of a magnet-type alternating-current generator 1 is constituted by a hybrid bridge circuit of a diode D1 or D3 and a thyristor Th. Output voltage Vin of the rectifying circuit 2 is inputted into the constant voltage power supply circuit 4 to be converted into constant voltage Vout, and the voltage Vout is given to the microprocessor 5A as power supply voltage. When the engine speed is below set engine speed, the thyristor Th is turned to be ON, and by making the rectifying circuit 2 perform full-wave rectifying operation, shortage of power supply voltage at low engine speed is prevented. When the engine speed exceeds the set engine speed, the thyristor Th is turned to be OFF, and by making the rectifying circuit 2 perform half-wave rectifying operation, voltage inputted into the constant voltage power supply circuit 4 is lowered to reduce the loss generated in a transistor TR1. COPYRIGHT: (C)2005,JPO&NCIPI

Load sensor and seat weight measuring apparatus with a plurality of strain gauges

Abstract: A load sensor hardly causing error in weight measurement even when the environmental temperature of the load sensor varies, and a seat weight measuring apparatus using the load sensor. The sensor includes a plurality of strain gauges form a bridge circuit. The strain gauges forming the bridge circuit are attached to the front and back surfaces of a base plate at substantially the same location. Portions of a flexible substrate, on which the strain gauges are formed, are folded and adhered to the back of the sensor plate with adhesive. The bridge circuit formed by the strain gauges compensates for the variation in resistance among the strain gauges generated due to the temperature distribution of the base plate, resulting in little or no variation in output.

Abnormality detector for converter, and abnormality detection method for converter

Abstract: PROBLEM TO BE SOLVED: To provide a detector and a detection method for a sensor capable of detecting easily each bridge side of a bridge circuit, disconnection of each cable connected to the bridge side or short-circuiting thereof. SOLUTION: In the abnormality detector for the sensor for detecting the sensor 11 comprising the bridge circuit, and the sensor for the disconnection of the each cable connected to the sensor 11 or the short-circuiting thereof, the respective sides of the sensor 11 are switched in order by a bridge side switching circuit 27 before measurement of a change in a physical quantity such as measurement of a strain, a voltage when a constant current flows in the bridge sides from a constant current source 28 is measured by a voltage measuring circuit 29, and a CPU 24 detects a disconnection state or/and short-circuiting state by a table in a storage means, based on a measured voltage, to be displayed on a display in a personal computer 30 or the like, by reception via a transceiving line such as a communication line or a radio line. COPYRIGHT: (C)2005,JPO&NCIPI

System and method of transferring data words between master and slave devices

Abstract: A data bus bridge circuit and method are provided for coupling a slave device with a data bus in a system in which data words are transferred between a master device and the slave device over the data bus. The bridge circuit removes master-induced stalls of burst transfers by converting those burst transfers into a plurality of separate, independent sub-bursts.

Load sensor and seat weight measuring apparatus

Abstract: A load sensor hardly causing error in weight measurement even when the environmental temperature of the load sensor varies, and a seat weight measuring apparatus using the load sensor. The sensor includes a plurality of strain gauges form a bridge circuit. The strain gauges forming the bridge circuit are attached to the front and back surfaces of a base plate at substantially the same location. Portions of a flexible substrate, on which the strain gauges are formed, are folded and adhered to the back of the sensor plate with adhesive. The bridge circuit formed by the strain gauges compensates for the variation in resistance among the strain gauges generated due to the temperature distribution of the base plate, resulting in little or no variation in output.

Bridge-buck converter with self-driven synchronous rectifiers

Abstract: A non-isolated bridge-buck DC-DC converter has self-driven synchronous rectifiers Q 5 Q 6 in the buck circuits 28 30 Gate electrodes of the synchronous rectifiers Q 5 Q 6 are connected to midpoints 24 A 24 B of the bridge circuit The voltage at the midpoints provides the necessary voltage waveform for switching the synchronous rectifiers Q 5 Q 6 In another aspect of the invention, voltage shift circuits 34 are provided between the midpoints and the gates of the synchronous rectifiers The voltage shift circuits are necessary in some embodiments to make sure that the synchronous rectifiers are turned completely OFF when necessary The present invention provides a more power efficient and less expensive technique for controlling the synchronous rectifiers compared to conventional external driver circuitry

Bridge for removing master-induced stalls on a data bus

Abstract: A data bus bridge circuit and method are provided for coupling a slave device with a data bus in a system in which data words are transferred between a master device and the slave device over the data bus. The bridge circuit removes master-induced stalls of burst transfers by converting those burst transfers into a plurality of separate, independent sub-bursts.

Mosgate device driver for synchronous rectification of a 3 phase sinusoidal source

Abstract: A rectifying circuit and method to produce a DC output by rectifying a sinusoidal source having a plurality of output phase voltages and a plurality of phase-to-phase voltages, the rectifying circuit including a bridge circuit coupled to the output phase voltages, the bridge circuit having a plurality of switches; and a control circuit coupled to the output phase voltages and to the bridge circuit, the control circuit being configured to control the switches in accordance with respective absolute values of the phase-to-phase voltages; wherein the output phase voltages are rectified to produce the DC output. When the sinusoidal source is inductive, switch turn-off may be timed to provide synchronous rectification related to estimates of source periodicity.

Research on a novel inverter based on DC/DC converter topology

Abstract: The conventional inverters have the shortcomings of straightway conduction in transistors and the difficulty of realizing soft switching. A novel inverter based on the DC/DC converter topology is presented and studied in this paper. The inverter is comprised of a combined buck/boost DC/DC converter and a bridge circuit. The front stage converter is controlled to output a variable DC voltage and the bridge circuit is to convert the DC voltage to an AC output. The energy feedback technology and one-circle-control scheme are used to improve the dynamic characteristics of the DC converter. The power devices of the inverter bridge can conduct soft switching. The operation principle and the circuit topology of this inverter are analysed. Simulations and experiments are conducted to demonstrate the performance of the proposed inverter.

DC system ground fault tester

Abstract: The utility model discloses a DC system grounding fault tester, which is suitable for on-line grounding fault test of the direct current 220V and negative 110V to positive 110V systems in power plants and transformer substations without external signal. The utility model properly solves the ground testing problem of the direct current system so as to effectively improve the reliability of power supply of the direct current system. A branch drain current testing circuit of a ground testing circuit is formed through that each branch of the direct current system is provided with a Hall transducer; the positive and negative buses of the direct current power respectively pass through the middle part of each Hall transducer after passing through a direct current breaker; a bridge circuit of the ground testing circuit is formed through that the positive and negative buses of the direct current power are provided with Hall bridges; the Hall bridge on the negative bus is connected with a first bridge resistance, and the Hall bridge on the positive bus is connected with a second bridge resistance; the other ends of the first and the second bridge resistances are connected and pass through the center of the Hall transducers used for checking the bus grounding and branch grounding so as to be grounded through a third bridge resistance 7.

Pulse power supply for regenerating magnetic energy

Abstract: A pulse power supply for regenerating the magnetic energy stored in a discharge circuit in a capacitor so as to use it as the next discharge energy and supplying a bipolar pulse current at high repetition rate. A bridge circuit is constituted of four reverse-conducting semiconductor switches. A charged energy source capacitor is connected to the DC terminal of the bridge circuit. An inductive load is connected to the AC terminal. A control signal is applied to the gate of each reverse-conducting semiconductor switch to turn off all the gates when the discharge current is increased, maintained, and decreased. As a result, by the thus control, the magnetic energy of the current can be automatically regenerated in an energy source capacitor by the diode action of the switches. By inserting a large-current power supply in the discharge circuit, the energy loss caused by discharge is compensated, enabling high-repetition rate discharge.

Optimized convection based mass airflow sensor circuit

Abstract: A method and apparatus for measuring the amount of flow of a flowing medium. The method and apparatus include a bridge circuit (20) configured to develop a bridge voltage Vb such that the magnitude of the bridge voltage Vb is indicative of the amount of flow. The bridge circuit (20) is configured without having an ambient temperature sensor, thus the bridge voltage is uncompensated with respect to ambient temperature. A thermistor circuit (54) is configured to generate a temperature reference voltage (56) indicative of ambient temperature. A conditioning circuit (50) is configured to receive the uncompensated bridge voltage and the temperature reference voltage (56) to process the same and generate a compensated bridge voltage with respect to ambient temperature. The compensated bridge voltage is indicative of fluid flow.

Inverter for converting an electric direct current into an alternating current or an alternating voltage

Abstract: Between two direct current (DC) connections in a parallel wiring structure there is a intermediate power store and a bridge circuit with two parallel branches (A/B,C/D), to each of which are wired rectifier diodes (DA,DB,DC,DD) in parallel. Certain rectifier diodes (DE,DF) link to each other in single connecting paths (9,10) in an opposed conducting direction. Each of two alternating current (AC) connections links individually via a connection node to one of the parallel branches between two switch units by means of a connecting wire, in which each has inductive chokes (L 1,L 2).

Differential pressure sensor

Abstract: Differential pressure sensor has a support (1) with a membrane (2) in its inner region that can be acted on from either side. Measurement resistances (3) are incorporated within the membrane and connected in a bridge circuit for measuring the pressure acting on the membrane, while compensation resistances (4) are formed on the support and connected in a second bridge circuit. Means are provided with which the pressure differential between the pressure acting on one side of the membrane (P 1) and the pressure acting on one end of the support (P 3) can be measured.

Inverter for an electric machine

Abstract: An inverter for an electric machine is specified that includes a plurality of switching elements, in particular six, which are positioned in a bridge circuit and produce a connection between the electric machine and a battery. The switching elements built into the low-side branch of the inverter are ones that are conductive without a control voltage present, i.e., normally-on switching elements. That ensures that if the supply voltage is absent and the electric machine is rotating the windings of the electric machine are short circuited and no overvoltages are able to occur. In normal operation the inverter is operated like a conventional inverter, by clocked actuation, but with reversed actuation of the control electrodes, i.e., with control voltage for non-conductive time phases and without control voltage in conductive phases.

Mutual inductance bridge for detection of degradation in metallic components

Abstract: An inductive bridge circuit using mutual inductances to transform impedances is used for detection of wall-thinning defects in metals. The bridge circuit has a first test coil placed adjacent to a good metal section and a second test coil placed adjacent to a metal to be tested. The bridge circuit compares the inductance in the first coil and inductance in the second test coil to compare wall thinning defects. The apparatus may also include first and second measuring transformers which are connected between the bridge circuit and the test coils where the transformers provide for impedance matching and reduced current requirements in the bridge. The circuit may also include one or more potentiometer circuits connected across the bridge which are used for compensating for imbalance of impedance between the first and second test coils when the coils both have known good metal sections adjacent to them.

Electric motor-driven power steering apparatus

Abstract: In an electric motor-driven power steering apparatus which comprises a bridge circuit for connecting a power source between input terminals and also connecting an electric motor between output terminals and energizes the electric motor by this bridge circuit and operates electric motor power to a steering system, the bridge circuit includes a predetermined number of arms constructed by connecting circuits for connecting switching elements in parallel with diodes in series so that the diodes mutually become reverse polarity.

Method for testing a sensor arrangement, especially a pressure sensor arrangement in an electronically regulated motor vehicle braking system, whereby provision of separable connections to a measurement bridge speeds operation

Abstract: The method is for testing a sensor arrangement that comprises at least one measurement bridge circuit (2, 2') that is electrically connected to an analysis circuit. The analysis circuit (1) is capable of implementing an error correction method which checks bridge circuits and connections by comparison of electrical output signals to design values or predetermined thresholds. An Independent claim is included for a test circuit arrangement.